Endless driving-belt.



C. ELOESSER.

ENDLESS DRIVING BELT.

APPLICATION FILED FEB. 3. 19m.-

1 1 86, 1 74 I Patented June 6, 1916.

Wncssea Mw M COLUMBIA 'PLANoanu-H cu., wAsmNa-rov D c UNITED STATESPATENT OFFICE.

CARL ELOESSER, OF CHARLOTTENBURG, GERMANY, ASS-IGNOR TO [Ill-I111. FIRM0F ELOESSER-KRAFTBANDGESELLSCHAFT M. 13. H., 0F CHARLOTTENBURG, GER-MANY.

ENDLESS DRIVING-BELT.

Specification of Letters Patent.

Patented J une 6, .1916.

Original application filed March 4, 1907, Serial No. 360,585. Dividedand this application filed February 3,

' 1912. Serial No. 675,313.

'is a specification.

The invention relates to driving belts, and more particularly to meansfor predetermining the required length of endless metal driving belts,such as described in my application for patent filed on March 4, 1907,

Ser. No. 360,585, of which this application is a division.

In the use of an endless metal driving belt it is of prime importancethat the belt be given exactly the required tension, as too great atension will be detrimental to the life of the belt and also to theshaft-bearing, while too small a tension will cause the belt to slip olfthe pulleys. In determining the tension allowance must be made for thesagging of the belt, especially where long belts are used, and it is,therefore, a diflicult problem to predetermine the tension of such adriving belt.

By describing my new tensioning device I will shov how the requiredlength of the driving belt and its exact tension can be predetermined,so that, when the belt is placed around the pulleys, its tension willneither be too large nor too small. For this operation a measuring bandof the same material as the driving belt but of smaller width andcross-section in combination with the tensioning device referred to ismounted on the pulleys intended for the driving belt, and after themeasuring band has been subjected to the required tension by saidtensioning device, its length may be measured by a suitable measuringdevice. In this way the length of the driving belt can be exactlypredetermined with a proper allowance for shortening due to the saggingof the belt, as the measuring band, though of smaller cross-section andwidth, will have the same sag as the driving belt. With the aid of mynew device one is, therefore, enabled to make driving belts of the exactlength within a fraction of a millimeter.

In order that my invention may be more clearly understood, reference ishad to the accompanying drawing, in which, by way of an example, oneform of a tensioning apparatus, as used for carrying out my invention,is illustrated, Figure 1 being a side elevation of the apparatus, partof the measuring device being shown in section, Fig. 2 a front elevationof the casing containing the measuring spring.

7 According to the drawing, the apparatus consists of two lever arms 0,(Z, connected by a post 6 and carrying at their free ends the clampingblocks a, 6, for holding the measuring band. Arm d is secured to post 6in fixed position by screws or the like, whereas arm 0 is held on thepost by a pivot pin 7", allowing said arm to be swung toward or awayfrom arm 03. The forward ends of the arms 0 and d are coupled by a screwbolt 9, on which is placed a nut k, so that upon tightening the latter,the free ends of the arms are moved toward each other, and the measuringband clamped by the blocks a and b is stretched. On the bolt 9 areplaced two disk-shaped abutments h, i, one below arm d, and the otherabove arm 0, each abutment being provided with a knife edge adapted toenter corresponding recesses in said arms. Against disk It abuts one endof a helical spring Z, which is inclosed in a cylindrical casing asupported by said disk, and the other end of which spring abuts againsta cylindrical cover 1?. adapted to telescope on said casing. The latteris provided with a graduated scale '1', whereby the tension of themeasuring band as measured by said spring Z will be indicated, as thelower edge of the cylindrical cover m moves over the said scale. Afterthe measuring band has thus been adjusted by the means of the thumbscrew 70 to the required tension, while the tension of the measuringspring has been observed on the scale 1', either of the two ends 0, 70,of the measuring band, one overlapping the other between the lever arms0, d, may be cut 05, and the remaining length be used to determine thelength of the driving belt.

Where the measuring band itself is provided" with a scale, the length ofthe belt can be easily ascertained by the measuring band, in which case,of course, the overlapping end of the latter is not cut off.

I claim as my invention:

1. A device adapted for application to pulleys in the manner stated,comprising a measuring band of the same material as, but of smallercross-section than the driving belt, clamping members for the ends ofsaid measuring band, means for tensioning the measuring band around thepulley, and means for measuring the amount of tension.

2. A device adapted for application to pulleys in the manner stated,comprising a measuring band of the same material as, but of smallercross-section than the driving belt, clamping members for the ends ofsaid measuring band, means adjustably connecting said clamping members,including a screw gear to tension the band around the pulley, and meansfor measuring the amount of tension.

3. A device adapted for application to pulleys in the manner stated,comprising a measuring band of the same material as, but

of smaller cross-section than the driving belt, clamping members for theends of said measuring band, adjustable levers carrying said clampingmembers, means connecting said levers including a screw gear, ameasuring spring controlled by said screw gear, and means for disclosingthe amount of tension.

4:. A device adapted for application to pulleys in the manner stated,comprising a measuring band made of the same material as, but of smallercross-section than the driving belt and provided with a scale, clampsfor the ends of said measuring band, adjustable levers carrying saidclamps, means connecting said levers including a screw gear, and ameasuring spring controlled by said gear.

In testimony whereof I hereto afiix my signature in presence of twowitnesses.

CARL ELOESSER.

Witnesses HENRY HASPER, lVOLDnMAR HAUIT.

Copies 0! this patent may be obtained for five cents each, by addressingthe Commissioner 0! Patents. Washington, D. G.

